Oil spills and releases of other water-borne pollutants can potentially result in grave environmental damage and health concerns. To help mitigate the adverse consequences of aquatic spills, oil containment booms or fences are used to isolate aquatic spills so that water-borne pollutants can be removed from the water.
Oil-containment booms include water-permeable, oil-impermeable curtains or bands connected together by connector spars to form an oil-containing wall. When placed in the water at an oil spill, booms are designed to assume and maintain a partially submerged, vertical position to contain oil floating on the surface of the water. Changing currents within the water, however, exert forces on the boom tending to rotate a boom to a position in which the bands or curtains are no longer vertical. This allows oil and other pollutants to escape the boom therebeneath.
Elongated flotation spars are connected to the surface of the curtains of a boom at points between the connecting spars to ensure that the boom maintains a generally vertical position in the water. Several different prior art booms with flotation spars connected along a side of the boom are disclosed by U.S. Pat. No. 3,764,015, issued Oct. 9, 1973; U.S. Pat. No. 4,116,833, issued Sep. 26, 1978; U.S. Pat. No. 4,333,726, issued Jun. 8, 1982; U.S. Pat. No. 4,248,547, issued Feb. 3, 1981; and U.S. Pat. No. 5,102,262, issued Apr. 7, 1992.
One problem with the above-identified and other known prior art booms is that the connections between the boom's bands and flotation spars do not allow for easy and secure replacement of a defective flotation spar. Adverse conditions during the containment operation may result in a flotation spar becoming damaged so that it no longer performs its function of maintaining the boom in a vertical position. Replacement of a damaged spar is necessary to prevent the spar from becoming a burden to the boom. Prior art booms, however, have flotation spars that are either fixedly attached to the containment band by a relatively complicated securement technique or else are not securely emplaced. As such, prior techniques do not provide effective spar attachments that also allow for easy replacement of a damaged spar.
A second problem arises as a result of the movement of water relative to the boom tending to lift the curtain which allows oil to escape therebeneath. Where the spars are relatively fixed with respect to the curtains, the spar itself may actually help create the drag that lifts the boom. As water speeds increase to 3 or 4 knots per hour, this problem may become more severe.